Refrigerating apparatus



Jan. 14, 1941.

Filed April 25, 1939 ATTORNEY.

Patented' Jan. 14, 1941 ulu'rlsol STATES Pli'rlfii'r OFFICE' v aEFmGEnArmG APrAnA'ms Lawrence `AL Philipp,4 Detroit, Mich., assignor to' Nash-Kelvinator Corporation, a corporation of Maryland Detroit, Mich.,

Application April 25, 1939, serial No. 269,996 4 claims. (ci. 23o-5s) This inventionrelatesto an improvement in refrigerating apparatus and particularly of the compressor type wherein provision is made for' cooling the compressor,

The invention consists of a sealed casing within which is housed a motor compressor unit, and

wherein the ldrive shaft of them'otor compressor -unit operates a centrifugal pump for delivering'v the oil collected in the sump to a-radiator or condenserv and then returns the cooled oil to thev 4arated therefrom.l Suitable vmeans is providedl for conducting the refrigerant from the chamber to theintake port of the compressor.

The invention consistsof certain other novel features of construction and combination of parts, which will be hereinafter described-and pointed out in the claims.

` In the accompanying vertical sectional view and partly in elevation',

illustrating an' embodiment of the invention.

In the construction shown,the compressor is preferably made ofacasting I wherein is formed a chamber II in' which the low pressure refrigerant is received and' the oil collected. 'I'he low pressure refrigerant from an evaporator is de- 'flivered to'chamber II, through an inlet port I2. Formed within the casting Ill` is a crank-caser i3 and a cylinder I4 which has communication with. the crank-case I3. A cover plate I5 is secured by bolt I6 to the top of the crank-case and the cover plate I5 andthe bottom of the casting are provided with suitable journals I1 and I3 for a drive shaft I9. Suitable bearings are provided in the journals II and I8 for the shaft I9. The drive shaft I9 is provided with an eccentric 22 on which is mounted an end of a pitman or connectingrod 23, the pitman-23 .being connected to a vpiston 25 which reciprocates within the cylinder I4. A suitable counterweight 25 is connected to the shaft I9.

Formed in' the base of the casting and beneath the crank-shaft is an oil well 28 which isclosed by means of a cover plate 29 suitably securedto the casting. The well 29 has communication with the chamber I I, by means of a passage 39 for supplying oil to the well. The drive shaft I9 extends into the well 29 and mounted on the shaft is a centrifugal 'pump 32.` The drive shaft at its lower adapted to be rotated drawing, Figure 1 is portion -of the casing or rotation of the motor and end is provided with a spiral groove on its outer surface 3,3 for ,conducting oil from the well 29 to the hollow passage 34 in the shaft I9. Suitable Aradial passages 35 are formed in this shaft and have communication with the passage 34 for conducting oil to the bearings v2i) and crank-case.

Mounted upon the casting'lii is-a stator 31 of an electric motor provided With'windings 38. A

rotor 39 is within the stator.' A hood or casing 49 envelops the electric motor and is mounted upon the drive shaft I9 `and provided with lan annular flange 4I at its base,

is supported upon an annularfiange 42 formed on the casting I Il. .ghe anges 4I and 42 .are connected together by nisans of bolts or other means for forming a hermetically sealed compartment for the motor compressor unit.

Mounted upon the rotor 39 isa dish like shield 44 which projects or flares over the windings 39. This shield is connected to the drive shaft I9 by means of the nut 45 which locks the rotor to the shaft I9. This shield is provided to prevent -the oil from owing down onto the motor, and

any oil that is collected in the shield from the low pressure refrigerant which is stored in the upper hood 4|),v will be thrown out of the shield by centrifugal force upon the openings 46 formed in the stator and between and along the walls into the chamber II.

will pass down through A low pressure refrigerantl receiving chamber;

or receptacle 48'is-mounted upon the rotor 39 and within the shield 44 and is connected to the drive shaft'by theanut 45 so'that this chamber 43 and the shield 44 will rotate in unison with the rotor. The receptacle or chamber 43 is open at itstop as at 49 for theingress of the low pressure refrigerant and is also provided with a plurality of orifices 59 in the walls thereof, through which lubricant may be discharged to the shield 44.

Upon the operation of the motor and compressor, low `pressure refrigerant is drawn from an evaporator (not shown) through the passage or inlet I2 into the chamber II. The refrigerant will be drawn upwardly into the hood or casing 49 and as it passes through the motor and openings 52 formed in the rotor 39, the oil will be separated to a large extent from the refrigerant and allowed to fall back into the chamber II. Some upper portion of the hood or casing 49 and enter into the chamber or receptacle 49.

A tube or piping 55 extends through the opening 49 of the receptacle 48 and projects a suitable distance within the receptacle. This tube forms a passage for the low pressure refrigerant and conducts it to a passage 56 formed between the stator 31 and the hood 40. 'Ihe refrigerant is conducted from this passage 56 into a passage 51 formed in the casting I0 and is delivered through a port 59 in the valve plate 58 positioned over the cylinder I4 and into a passage 60 formed in the cylinder head 62. -The valve plate 58 is provided With a port 63, normally closed by a reed valve 64. However, upon theV suction stroke of the piston 25, this valve is opened and the low pressure refrigerant is drawn from the passage 51 and through the port 63 into the lcylinder I4. The cylinder head 62 is provided with a passage 65 which has communication with the cylinder I4 through a port 66 formed in the valve plate 58. 'I'his ,port 66 is normally closed by a valve 61 but upon the compression of the refrigerant by the piston, this valve is unseated and the compressed refrigerant will be delivered into the passage 65 Where itis delivered to a passage 68 formed in the base of the casting I0. From the passage 68, the refrigerant is conducted to a condenser (not shown), where the refrigerant will be liquefied and then conducted through suitable valve means before being delivered to an evaporator. Y

During the refrigerating cycle, a quantity of oil is collected in the chamber II, and -to cool this oil and to utilize it for cooling the motor, the oil is conducted from the chamber I I by the passage 30 to the well 28 where the centrifugal-pump 32 will discharge the oil from the well through a conduit 10 connected to the well and deliver it to a radiator or condenser 1I. The radiator or condenser is here shown as made up of sinuous tubing 13 and into which the oil is delivered and cooled by any suitable means such as a fan, water or what not. The oil is delivered from the condenser 'II through a conduit 14 which extends into and through the hood or casing 40. The oil is delivered over the stator 31 and drains back into the compartment I I through the passages 46 and in this manner, effects a cooling of the motor. A suitable baille 16 is mounted upon the stator for preventing the oil from getting onto the rotor 39 and an overflow pipe 11 is also provided in the stator 31 for forming an additional means for conducting the oil into the chamber I I.

From the foregoing, it will be `observed that' provision is made for removing the oil from the casing housing and the motor compressor unit, by means of a centrifugal pump and delivering it to a condenser oi` radiator located exteriorly of the casing, Where the oil may be cooled and returned to the casing in a cooled condition for cooling the motor. Furthermore, provision is made for collectingany oil that may become separated from the low pressure gas as it is de- A livered into the upper portion of the hood of casing 40 and from. which the oil is discharged by' centrifugal force due to the' rotation of the motor A and this oil is returned to the chamber II, through the passages 46 formed in the stator.

The provision of the chamber 48 into which the low pressure refrigerant is delivered prior to its delivery to the cylinder I4, also rotates .with the rotor and any oil which may be contained Within the .refrigerant will be extracted therefrom, due to the rotary motion imparted to the chamber receptacle 48, so that the refrigerant is Vfreed to a large extent of the oil before its delivery to' the compressor. This chamber also acts as a muffler in reducing the noise due to the suction created by the compressor in drawing the low pressure refrigerant into the cylinder I4.

The oil separated from the refrigerant in the receptacle 48 is delivered tothe shield 44 through the orifices 50, and this separated oil is discharged from the shield by centrifugal force over the stator and beyond the baille 16, where it may drain into the chamber II through the passages 46 As will be noted overow pipe 'I'I is larger in diameter than holes 46 and in the event more oil is pumped to the top of the motor than will pass `through holes 46 the remainder will pass through the overflow 'I1 to the reservoir below.

Although only a preferred form of the invention has been illustrated, and that form described in detail, it will be apparent to those skilled in the art that various modicationsmay be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. In a refrigerating apparatus a casting havling a low pressure refrigerant and oil chamber and a compressor chamber, a compressor mountrefrigerant, said motor causing separation of entrained lubricant from the low pressure refrigerant by centrifugal action as the refrigerant passes through said motor, said separated low pressure refrigerant being directed to the top of said casing and the oil into the oil chamber of the casting and a receptacle carried bysaid motor having communication with said casing for receiving the separated low pressure refrigerant and means associated with said receptacle for conducting the low pressure refrigerant to the compressor.

2. In a refrigerating apparatus, a casting having an oil chamber and a .compressor chamber formed therein, a compressor mounted in saidcompressor chamber, a motor` mounted upon said casting, a drive shaft for said motor and compressor, a casing connected to said casting for enclosing said motor and providing a chamber between the top thereof and said motor for the low pressure refrigerant, a shield disposed over said motor and connected to said drive shaft, a receptacle disposed over said motor and connected to said drive shaft for receiving low pressure refrigerant and oil from said casing chamber, said receptacle being-subjected to rotary motion by said motor and causing a separation by centrifugal force of the oil from said refrigerant, said oil being delivered into said shield and discharged from said shield due to the rotation of the shield with the motor, and means associated with said receptacle for conducting the low pressure refrigerant to the compressor.

3. In a refrigerating apparatus a casting -having a crankcase and a cylinder of a compressor formed therein and an oil and a low pressure refrigerant chamber arranged about said crankcase, means for delivering low pressure refrigerant to said chamber, a piston movable in said cylinder, a drive shaft journaled in said crankcase for operating the piston, an electric motor connected tojsaid drive shaft, a hood for enclosing said motor and connected to said casting, said motor causing 'separation of entrained lubricant from the low pressure refrigerant by centrifugal motor, saidfseparated low pressure refrigerant being directedto the top ot said hood, a recep- -V tacie carried by said motor having communication with said hood for receiving the separated refrigerant, and means for conducting the ref' frigerant from said receptacle to the cylinder. 4. In a reh'igerating apparatus, a casing having a low pressure refrigerant andl oil chamber,

pumping mechanism and an electricmotor mounted in said casing; said motor causing a separation by centrifugal'actin of the oil from the low pressure refrigerant as the 'rea f'rigerant passes through said motor, a receptacle mounted upon and rotating with said motor for Vreceiving the separated low pressure refrigerant.

and means'tor conducting the refrigerant from said lreceptacle to said pumping mechanism.

* LAWRENCEA PmuPP, 

